GPT-4o vs GPT-5 mini
GPT-5 mini is cheaper for every workload modelled here.
List prices checked
Specifications and rates
| Property | GPT-4o | GPT-5 mini |
|---|---|---|
| Input per 1M | $2.50 | $0.250 |
| Output per 1M | $10.00 | $2.00 |
| Cached input per 1M | $1.25 | $0.025 |
| Blended (3:1) | $4.38 | $0.688 |
| Context window | 128K | 400K |
| Max output | 16K | 128K |
| Inputs accepted | text, image, audio | text, image |
Source: OpenAI pricing (May 2026) · OpenAI pricing (May 2026). Published list prices only — committed-use discounts, regional variation, and per-request charges are not included. Not yet independently re-checked against the vendor’s page.
Monthly cost by workload
Identical token volumes through both rate cards. Output-heavy profiles are where the ranking flips.
| Workload | GPT-4o | GPT-5 mini | Cheaper |
|---|---|---|---|
| In-app chat assistantA support or help assistant handling a few thousand conversations a month, with short prompts and short answers. | $100 | $15 | GPT-5 minisaves $85/mo (85%) |
| RAG over documentsRetrieval-augmented answering where each request stuffs several retrieved passages into the prompt, so input dominates. | $900 | $105 | GPT-5 minisaves $795/mo (88%) |
| Coding agentAn agentic loop that reads files and writes patches, generating heavy output and re-sending large context on every turn. | $2,000 | $300 | GPT-5 minisaves $1,700/mo (85%) |
What each one is for
GPT-4o
by OpenAI
The natively multimodal model that set the mid-market price for over a year. Now more expensive than newer models that outperform it, but still the default in a great deal of shipped code.
GPT-5 mini
by OpenAI
A fifth of GPT-5's price with the same 400k context window, which makes it the cheapest way to process very long documents without dropping to a small model.
Common questions
- Is GPT-4o or GPT-5 mini cheaper in 2026?
- GPT-5 mini, for every workload modelled here. On a blended 3:1 basis it costs $0.688 per million tokens against GPT-4o's $4.38.
- Which has the larger context window?
- GPT-5 mini, at 400K tokens against 128K. A larger window only helps if you can afford to fill it — the cost of one full-context request is in the table above.
- Which is cheaper for output-heavy work like agents?
- GPT-5 mini, at $2.00 per million output tokens against $10.00. Reasoning tokens bill as output, so for agentic loops this axis usually decides the invoice regardless of what the input rates look like.
- What is not included in these figures?
- Batch-processing discounts, fine-tuning, long-context surcharges above a provider's standard tier, and any enterprise agreement. These are published pay-as-you-go list prices, checked against each provider's own pricing page on the date shown.